Have you ever played any adventure games? They can always open the institutions when the
enemy enters their private territory. How does this work? In fact, this is the role of intrusion
alarms. Through this experiment, we will teach you how to make your own intrusion alarm, and
quickly put it in your private space to protect your own space!
Experiment 8 – Intrusion alert
Instruction
Learn how PIR motion sensor works and use it to make an intrusion alarm with buzzer.
Learn how to clear Micro:bit’s matrix LEDs.
Micro:bit x1
Crowtail-Base shield for Micro:bit x1
Crowtail-PIR Motion Sensor x1
Crowtail-Buzzer x1
Crowtail-Cable x2
USB cable x1
Target
Required Parts
Crowtail- PIR Motion Sensor(Passive Infrared Sensor) can
detect infrared signals caused by motion. If the PIR sensor
notices the infrared energy, the motion detector will be
triggered and the sensor outputs HIGH on its SIG pin. The
detecting range can be adjusted by a potentiometer
soldered on its circuit board, the max detecting range of it
up to 6 meters.
P0 is a port with pull-down, please do not connect PIR motion sensor to this
port! For the micro: bit, when the PIR module detects an object movement, it will change from
low level to high level and output high level continuously for 5 seconds, which means you don't
need to set extra delay.
Connect Crowtail-PIR Motion Sensor and Crowtail-Buzzer to P2 and P1 ports of Crowtail-Base
shield for Micro:bit. The hardware connections are as follows:
Hardware learning and connection
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